could be prepared from cholesterol acetate in two steps. The only uncertainty at this stage would be the effect of the chlorine atom at position 5 on the microorganism. However, the presumed intermediate, 0chloro ketone, should eliminate HCl easily even in the fermentation medium. When 1.1 g. of V was exposed to CSD-10 for 80 hr., 250 mg. (36%) of I, m.p. 179-182”, was obtained. Surprisingly, 3-hydroxycholesta-l,3,5(10)-triene (VI) was not metabolized by CSD-10. l 3
w
/+@
9
HOHzC AcO
w
Table I.
Induction and Specificity of Ring Cleavage Enzymes relative activity
Inducer
Substrate
Aa
B”
Androstenedione Androstenedione Cholestenone Cholestenone
Androstenedione Cholestenone Cholestenone Androstenedione
100
100
